Adjust hydrax to a metric system


03-03-2009 07:29:10

Hi I'm using projected grid vertex (best fps resoult) + perlin, and I try to adjust it to a system where 1.0 unit = 1 meter. I've been playing around with hydrax editor:
- reduced strength
- increased fall off
- reduced scale
- reduced animation speed
Looks almost good, but "almost" makes a huge difference ;) The waves seem hmmmm low-poly. I know I could increase the complexity, but this had an impact on the fps. So what came into my mind would be to:
- scale the projected grid along view-space* Z coordinate, since I don't need the water to be drawn in the distance of thousands-millions of kilometers.
- adjust the view-space* Z complexity (probably decrase the total complexity, but since the grid is scaled down it will still resoult in an increased complexity per meter), and increase the view-space* X complexity.

* view-space - not really vs, since we don't want to be affected by the cameras pitch/roll. Rather a system of (x,y,z) * camera.yawQuaternion.

Would it be possible to get the mentioned tweak working ? If yes: how ?


03-03-2009 09:06:47

Try to set a little value of Elevation Projected grid option before trying to tweak the projected grid module.
Hydrax must look the same in all(reasonable) world-units scale(And setting the correct parameters).



03-03-2009 09:23:45

Does it work in the editor ? I can see no difference between 0, 10 or 50
edit: ok it works. just need to move ;)
I will play around and post the effect.


17-04-2009 20:57:09

Nargil, did you ever get this to work? Changing elevation from 50 to 1, I see no diffrence whatsoever. What does it do exactly? Did you ever manage to get it to work with a scale of "1.0"?




17-04-2009 21:20:48

Ok ive worked it all out except the water texture appears to be very "segmented". Ive checked in wireframe, The polycount is fine after setting elavation to 1, But there's some texture which is not scaling correctly. Ive tried all the texture size options, And i see no change to the "segmentation" when i change everything to 128x128.

Any help would be much appreciated




05-05-2009 14:17:36

Hey guys

I am having some similar issues to you in that i can not get it to work perfectly in a smaller scale. Any chance you could post your hydrax config files so we can compare results!??




05-05-2009 15:00:37

I know what's happening, The rtt texture resolutions are too low, For the size of the projected grid. This does not matter when you are further away from the surface, But if you get close u notice the lack of texture detail. Ive tried changing the uv's, But that did not work, as it made reflections etc half the size of what they should be. I think what i need to do is decrease the max view distance, So the projected grid is smaller, Thus decreasing the amount of geometry the texture has to cover. At the moment, Im having second thoughts about hydrax, As on the surface, When set up exactly as it is as default in the editor, It looks great, But the instant you do anything real with it i.e, Put it in a game, You suddenly notice a lot of bugs. Another problem with setting the scale to 1.0, Seems to be that the depth textures are extremely inaccurate, So much so that it looks like there are infact simply two objects above the water, Then suddenly they both dissapear. I will post a post telling xavi about the bugs i have come across, And see if he has plans to fix it, however it seems atm like xavi is concerntrating on skyx. He posted that he would be working on the next version of hydrax over summer, But thats a while away. Ill see what infomation i can get off him, Then i will decide weather to continue using hydrax or not.

Oh heres the configuration settings i use, For FFT. It works fine, appart from the bugs i have already mentioned.

#Hydrax cfg file.

#Hydrax version field

#Main options field
#Shader mode: 0=HLSL, 1=CG, 2=GLSL

#Components field

#Sun parameters

#Foam parameters

#Depth parameters

#Smooth transitions parameters

#Caustics parameters

#God rays parameters

#Rtt quality field(0x0 = Auto)

#Module options


#Noise options




19-10-2009 13:25:06

I'm also working with a system where 1Ogreunit = 1 meter and having trouble getting Hydrax to work nicely.
It would be nice if Hydrax were attached to a node and you could just scale it all in one go...